When people think of Roth options, most think of a Roth IRA. Even though 95% of employers offer a Roth 401(k) plan, less than 20% of employees take advantage of it.

I worked as a consultant in the retirement industry for decades and I was part of the 80% that didn't contribute to Roth in my 401(k). Almost five years into retirement, it's one of my biggest regrets.

The statistics show that, like me, most people continue to contribute pretax to their 401(k). They don't question the conventional wisdom that their tax bracket is probably higher while they're working than it will be in retirement. They take the deduction now and defer the income tax until retirement when they're likely in a lower bracket. It makes sense.

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